<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    var o = {
        a:'aa',
        b:'bb'
    }
    o = {
        c:'cc'
    }
    console.log(o);
</script>
</body>
</html>